Hi Ex-NISH2
The IF-RIO trigger is exactly the same as the DIO terminals, with the exception that the trigger is connected to a SMB on the panel, instead of the multi-pin connector.
Look at the ni5640R Digital IO example that ships with the ni5640R software.
To use the trigger line, in the LabVIEW project, right click on the FPGA Target and select New>>FPGA I/O and select the trigger. This will add the trigger I/O to the LabVIEW project.
Programmatically, use the trigger the same way that the DIO terminals are used in the example.
As for what the trigger does, that is up to you and how you program your FPGA, there isn’t any default trigger “functionality” for the trigger.
Jerry
